1. Field of the Invention
The present invention relates to a food processor of the citrus press or juicer type.
2. Description of the Related Art
This type of food processor generally comprises a base unit which supports drive means which comprise, amongst other things, a rotary spindle. In use, this spindle drives an active food processing implement. When the processor is a citrus press, this implement is a cone against which the fruit, generally cut into two, is pressed. Furthermore, in the case of a juicer, this active implement is generally a grater against which the food product is pushed so that it can be shredded.
There are, firstly, known citrus presses in which the cone rotates continuously. However, this solution is somewhat inconvenient inasmuch as the pressing operation becomes awkward to implement. In addition, it may in some instances prove dangerous to the operator.
To solve this problem, citrus presses have also been produced in which the rotation of the cone is switched on electrically. More specifically, when the fruit is pressed, the force thus used plays a part in closing an electrical contact switch, allowing the motor to be switched on.
When the citrus press is provided with a lever arm for pushing the fruit against the juice-extracting cone, this contact switch is usually positioned on the actual lever itself. There are also other types of citrus press, usually “manual” ones. This contact switch is then positioned according to a translational movement of the juice-extracting cone or of the spindle thereof.
This type of citrus press, that involves an electric contact switch, is, however, accompanied by its own special disadvantages. Specifically, this electrical switch-on entails the use of a motor with a high start-up torque. In addition, this solution is accompanied by frequent startings and stoppings of the motor, particularly during intensive use. As a result, this leads to a reduction in the life of the processor, the number of cycles of the electrical component being inherently limited.
Furthermore, when the motor is switched on electrically, a ramp of acceleration is needed before the nominal extraction speed is reached. Likewise, there is a ramp of deceleration immediately after the motor stops. It will be readily appreciated that this is going to slow down the juice-extracting operation, which is disadvantageous from an economical standpoint, in an industrial setting. In addition, because of the inertia of the various components, there is a period of latency during which the cone is not in the stopped position, and this may cause splashing, together with discomfort or even danger to the operator.
In order to address the disadvantages of this alternative solution, the applicant company has proposed a citrus press of the disengageable type, marketed under the reference No. 10. This processor calls upon a motor that is in continuous operation but which drives the juice-extracting cone only when a pressing force is applied to this cone.
To this end, there is an intermediate member that can be driven by the motor selectively, so that this member has an inactive rest position, and an active drive position. The movement from the rest position to the drive position occurs when a pressing force is applied to the cone, whereas elastic return means tend to return the intermediate member to the rest position when this force is no longer applied.
More specifically, this drive member is in the form of a shaft secured to the cone, which is mounted in an end plate secured to the base unit, with bushings interposed between them. This shaft is extended by a plate able to rest against a rotary platen belonging to the drive means when the pressing force is applied. When this happens, the driveshaft is set in motion, playing a part in causing the cone to rotate. In addition, when this force is released, a return spring pushes the plate back against the end plate secured to the base unit, causing the driveshaft and the cone to stop.
This last solution has numerous advantages, which have led to significant commercial success over a good many years. However, it has been found that this processor No. 10 had a relatively short life, and that some of its constituent parts had to be renewed relatively frequently. In addition, a processor such as this requires a fairly high number of components.